Failure envelops analysis for square mudmat foundations on undrained clays under three-dimensional loading

As the permanent submarine support structures for subsea wells, pipeline manifolds and pipeline terminations, the mudmat foundation works under obviously complex, nonlinear and uncertain loading, which makes a great challenge for the research of the stability of mudmat foundation. In this paper, finite element method is utilised to investigate the behaviour of square mudmat foundation without embedment in NC clay to fully 3D loading conditions: V-H-M and V-H-T. According to the analysis results, the relevant failure envelop surfaces and formulas are proposed to predict the capacity of mudmat foundation. These results could be treated as reference for the design work of the mudmat foundation.